Simulating the Climatic Impact on Vehicle Engine Function Parts

2021 ◽  
Vol 105 (1) ◽  
pp. 531-539
Author(s):  
Tomáš Binar ◽  
Jana Zimáková ◽  
Pavel Šafl ◽  
Marie Sedlarikova
Keyword(s):  
Laboratory Tests ◽  
Limit State ◽  
Degradation Process ◽  
Climatic Conditions ◽  
Notch Toughness ◽  
Open Area ◽  
Climatic Impact ◽  
Vehicle Engine ◽  
Functional Part ◽  
Number Of Cycles

The paper describes the assessment of the influence of climatic conditions, temperature and relative humidity on the lifespan of the cylinder forming the functional part of the vehicle TATRA 815 6x6 VVN. Based on the measured notch-toughness value in the test temperature range -80 °C to +100 °C, the corrosion effect on specimens with and without corrosion protection was evaluated. A condensation chamber was used to simulate corrosion conditions which can cause corrosion and degradation process in the material leading to lifetime reduction and limit state development. The duration of the corrosion laboratory tests in the condensation chamber considered the real time when the TATRA 815 6x6 VVN vehicle is exposed to climate change on an open area in the fleet. There were three sets of samples for simulations with different number of cycles (9, 18 and 27 cycles).

Some Regularities of Life Time and Damage for the New Structural Material MoNiCa during Sliding Friction and Mechano-Sliding Fatigue

2021 ◽  
Vol 320 ◽  
pp. 90-96
Author(s):  
Aliaksandr Bahdanovich ◽  
Sergei Sherbakov ◽  
Ivan Lis ◽  
Regita Bendikiene ◽  
Ramūnas Česnavičius ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Structural Material ◽  
Mechanical System ◽  
Sliding Friction ◽  
Limit State ◽  
High Strength ◽  
Life Time ◽  
Average Wear ◽  
The Republic ◽  
Number Of Cycles

The results of an experimental study of damage for the structural material MoNiCa (it is high-strength cast iron VCHTG – patent of the Republic of Belarus № 15617) on sliding friction and mechano-sliding fatigue are analyzed in the report. Tests of the mechanical system shaft (a sample with a working part diameter of 10 mm made of 0.45 % carbon steel) - an insert (a prismatic counter sample with a cross section of 10 ´ 10 mm made of MoNiCa) were carried out. The kinetics of the change in average wear at 8 local points along the perimeter of the dangerous area of the sample is given for contact loads FN from 20 to 92 N of the mechanical system under study with MoNiCa inserts without heat treatment and with heat treatment. The test results of the system under study are also presented in the form of sliding friction and mechano-sliding fatigue curves in coordinates of the contact load FN – the number of cycles N until the limit state.

Influence of Natural and Climatic Factors on Water Horizons Protection Degree in Site Evaluation for Radioactive Waste Disposal

2021 ◽  
Vol 24 (3) ◽  
pp. 301-310
Author(s):  
N. V. Harbachova ◽  
N. D. Kuzmina ◽  
N. V. Kulich ◽  
S. N. Yatsko ◽  
J. A. Korchova
Keyword(s):  
Radioactive Waste ◽  
Climatic Factors ◽  
Probabilistic Approach ◽  
Groundwater Vulnerability ◽  
Climatic Conditions ◽  
Radioactive Waste Disposal ◽  
Climatic Impact ◽  
Influence Zone ◽  
Site Evaluation ◽  
Numerical And Analytical Methods

In this paper, natural (geological and hydrological) and climatic impact conditions on the influence zone for two different sites of radioactive waste disposals have been studied. Probabilistic approach to assessment of the groundwater vulnerability from radionuclide contamination during disposal of radioactive waste is developed. As to climatic conditions, an effective numerical and analytical methods for annual precipitation rates assessment of rare recurrence have been proposed which allow to take into account uncertainties of rare events as well.

scholarly journals Surface Changes of Selected Hardwoods Due to Weather Conditions

Forests ◽  
2018 ◽  
Vol 9 (9) ◽  
pp. 557 ◽  
Author(s):  
Ivan Kubovský ◽  
Eliška Oberhofnerová ◽  
František Kačík ◽  
Miloš Pánek
Keyword(s):  
Laser Scanning ◽  
Weather Conditions ◽  
Degradation Process ◽  
Climatic Conditions ◽  
Laser Scanning Microscopy ◽  
Dust Particles ◽  
Confocal Laser ◽  
Chemical Changes ◽  
Colour Changes ◽  
Surface Changes

The study is focused on the surface changes of five hardwoods (oak, black locust, poplar, alder and maple) that were exposed to natural weathering for 24 months in the climatic conditions of Central Europe. Colour, roughness, visual and chemical changes of exposed surface structures were examined. The lowest total colour changes (ΔE*) were found for oak (23.77), the highest being recorded for maple (34.19). Roughness differences after 24-month exposure (ΔRa) showed minimal changes in poplar wood (9.41); the highest changes in roughness were found on the surface of alder (22.18). The presence of mould and blue stains was found on the surface of maple, alder and poplar. Chemical changes were characterized by lignin and hemicelluloses degradation. Decreases of both methoxy and carbonyl groups, cleavage of bonds in lignin and hemicelluloses, oxidation reaction and formation of new chromophores were observed. In the initial phases of the degradation process, the discoloration was related to chemical changes; in the longer period, the greying due to settling of dust particles and action of mould influenced the wood colour. The data were confirmed by confocal laser scanning microscopy. The obtained results revealed degradation processes of tested hardwood surfaces exposed to external environmental factors.

scholarly journals THE INFLUENCE OF CLIMATE ON THE RESPIRATORY FUNCTION OF THE HEALTHY POPULATION OF VLADIVOSTOK AND PATIENTS WITH BRONCHOPULMONARY PATHOLOGY

2018 ◽  
Vol 97 (5) ◽  
pp. 418-423
Author(s):  
L. V. Veremchuk ◽  
E. E. Mineeva ◽  
Tatyana I. Vitkina ◽  
T. A. Gvozdenko
Keyword(s):  
Respiratory Function ◽  
Pulmonary Ventilation ◽  
Weather Conditions ◽  
Climatic Conditions ◽  
Bronchial Obstruction ◽  
Healthy Population ◽  
Uncontrolled Asthma ◽  
Monsoon Climate ◽  
Climatic Impact ◽  
The Impact

Introduction. The climatic factors affect the mucous membrane of the respiratory tract contacting with the environment. The investigation of pulmonary ventilation plays a leading role in the diagnosis of bronchial obstruction in response to an external stimulus. Material and methods. The study included a healthy population of the city and patients with chronic catarrhal nonobstructive bronchitis (CCNB), controlled and uncontrolled asthma (131 people). The respiratory function (RF) was estimated by spirography and body plethysmography. Meteorological conditions were evaluated from the point of view of contrasting weather changes (on the survey day, on 1st and 2nd days before the survey). The degree of the climatic impact on RF was determined by the statistical module “Discriminant analysis”, used to a group of RF indices relatively adverse levels of impact of the monsoon climate. Results. The low level of the responsiveness in a healthy urban population was identified. The negative impact of climatic indices on the respiratory system in CCNB patients was observed mainly in extreme weather conditions. The influence of climatic conditions on patients with asthma depends on the level of the disease control. Discussion. The influence of climatic conditions was found to be within the adaptive and compensatory responses in a group of healthy people and CCNB patients. We assumed the use of basic drugs in patients with asthma without signs of bronchial obstruction to reduce the susceptibility of the receptors of the bronchi to the negative climatic impact. The greatest negative RF response to the impact of monsoon climate manifested both in static and in dynamic weather conditions, was observed in patients with uncontrolled asthma. It was associated with the impaired pulmonary ventilation. Conclusion. The results indicate the Far East monsoon climate to be an important risk factor for the exacerbation in patients with respiratory diseases.

A Study on the Influences of Crumb Rubber Modified Asphalt

2012 ◽  
Vol 204-208 ◽  
pp. 3899-3904
Author(s):  
Lan Yun Chen ◽  
Qing Long You ◽  
Xin Qiu
Keyword(s):  
Laboratory Tests ◽  
Mechanical Characteristics ◽  
Engineering Application ◽  
Crumb Rubber ◽  
Climatic Conditions ◽  
Pavement Performance ◽  
Rubber Content ◽  
Modified Asphalt ◽  
Truck Tire

In order to study the effects of different factors on the performance of crumb rubber modified asphalt, on the basis of many laboratory tests, this article analyzed such factors as types of crumb rubber, fineness, content, mixing temperature and matrix asphalt. Results show that mixed with the crumb rubber, pavement performance of the asphalt has been improved to varying degree. In the engineering application of rubber asphalt, it is suggested that the 20 mesh crumb rubber modified asphalt of truck tire be adopted, with about 16% to 18% of crumb rubber content at about 175°C. As for matrix asphalt, it should be selected according to the different climatic conditions and the mechanical characteristics of the pavement.

Failure Analysis of a Shaft Belonging to a Ship Engine Speed Controller

1999 ◽  
Author(s):  
Miguel V. Figueiredo ◽  
Fernando M. Oliveira ◽  
Paulo T. de Castro ◽  
António A. Fernandes
Keyword(s):  
Electron Microscopy ◽  
Fracture Surface ◽  
Failure Analysis ◽  
Laboratory Tests ◽  
Engine Speed ◽  
Notch Toughness ◽  
Severe Damage ◽  
Speed Controller ◽  
Service Conditions ◽  
Scanning Electron

Abstract The fracture of a shaft belonging to the speed controller of a ship’s engine is presented. An over-speed situation occurred as a result of the fracture of this shaft, which led to severe damage to the engine. The failure examination concentrated first on the study of the available evidence, which included the analysis of the shaft’s material and fracture surface. The shaft’s material was studied as concerns chemical composition, mechanical properties and micrographic structure. The fracture surface was studied using scanning electron microscopy. Several different destructive laboratory tests were conducted on the material, in order to obtain fracture surfaces which could be used for comparison purposes, and thus help to identify the cause of the fracture. The next step of the failure analysis consisted of a stress analysis of the shaft under service conditions. A probable scenario for the failure was proposed, which helped the interested parties to reach an agreement concerning responsibilities for the failure. It was found that the shaft material presented low notch toughness. The stress levels at the time of the accident imply that it is unlikely that the fracture was due to fatigue. The probable cause of the failure was sudden blockage of the shaft.

Assessment of Products Future Reusability Based on Consumers Usage Behavior: Implications for Lithium-Ion Laptop Batteries

2015 ◽  
Author(s):  
Mostafa Sabbaghi ◽  
Behzad Esmaeilian ◽  
Ardeshir Raihanian Mashhadi ◽  
Willie Cade ◽  
Sara Behdad
Keyword(s):  
High Reliability ◽  
Lithium Ion ◽  
Degradation Process ◽  
Rechargeable Batteries ◽  
Data Set ◽  
Utilization Behavior ◽  
Product Reuse ◽  
Number Of Cycles ◽  
Stability Time ◽  
Product Durability

Product reuse is a recommended action toward sustainability. However, the profitable reusability of End-of-Use or End-of-Life (EoU/L) products depends on how consumers have used them over the initial lifecycles and what are their EoU conditions. In addition to consumers’ behavior, product design features such as product durability has an impact on the future reusability. In this paper, a data set of Lithium-ion laptop batteries has been studied with the aim of investigating the potential reusability of laptop batteries. This type of rechargeable batteries is popular due to their energy efficiency and high reliability. Therefore, understanding the lifetime of these batteries and improving the recycling process is becoming important. In this paper, the reusability assessment is linked to the consumer behavior and degradation process simultaneously through monitoring the performance of batteries over their lifetimes. After capturing the utilization behavior, the performance-based stability time of batteries is approximately derived. Consequently, the Reusability Likelihood of batteries is quantified using the number of cycles that the battery can be charged with the aim of facilitating future remarketing and recovery opportunities.

Service Life of Concrete Structures

2020 ◽  
Vol 309 ◽  
pp. 267-271
Author(s):  
Milan Holicky ◽  
Jiří Kolísko
Keyword(s):  
Service Life ◽  
Concrete Structure ◽  
Limit State ◽  
Concrete Structures ◽  
Technical Specification ◽  
Working Life ◽  
Degradation Process ◽  
International Standards ◽  
Limit States ◽  
Existing Structures

The concept of service life of structures is included in international standards ISO (under the term Design Working Life), in the European document EN 1990 (Design Service Life) and in the upcoming document CEN for assessment of existing structures - Technical Specification TS (Remaining Working Life). The mentioned documents contain mainly material-independent provisions for the design and assessment of all types of structures and for any category of actions. The submitted paper includes the definition of service life (performance time) tser, which is extended for any concrete structure, considering the resistance of a structure R(t) and the effect of action S(t). Both the aggregate variables R(t) and S(t) are usually random variables significantly dependent on time t. Due to the random variability of the variables R(t) and S(t), the service life tser, needs to be related to the probability that the performance of the structure is weakened or completely eliminated. Basically, serviceability limit states (SLS) and ultimate limit states (ULS) should be considered. In the case of concrete structures another limit state corresponding to the beginning of a specific degradation process (corrosion of reinforcement), denoted tinit, may be important. In specific cases of buildings and bridges a functional (moral) service life may be taken into account. The paper includes also a practical example of assessing the remaining working life of a concrete structure.

Cyclic axial loads on piles: Analysis of existing data

1986 ◽  
Vol 23 (3) ◽  
pp. 362-371 ◽  
Author(s):  
Jean-Louis Briaud ◽  
Guy Y. Felio
Keyword(s):  
Data Base ◽  
Laboratory Tests ◽  
Ocean Waves ◽  
Cyclic Behavior ◽  
Axial Loads ◽  
Soil Stiffness ◽  
Model Pile ◽  
Load Tests ◽  
Pile Load Tests ◽  
Number Of Cycles

A data base is collected to study the behavior of piles in clay under cyclic axial loads generated by ocean waves. The data base includes 9 studies on the cyclic behavior of clay samples in laboratory tests, 10 studies on cyclic model pile load tests in clay, and 16 studies on cyclic full-scale pile load tests in clay of which 4 studies are proprietary. First, general conclusions are drawn from inspection of these studies. Then a power law model is used to quantify the soil stiffness degradation as the number of cycles increases. The parameter for the model is back-figured for each case of the data base and general trends are observed. Key words: pile load tests, cyclic loads, laboratory tests, clay.

scholarly journals Analysis of the criteria for calculating non-rigid pavements in conditions of intense traffic flow

2018 ◽  
Vol 5 (3) ◽  
Author(s):  
Evgenia Uglova ◽  
Olga Shilo
Keyword(s):  
Life Cycle ◽  
Asphalt Concrete ◽  
Building Materials ◽  
Climatic Conditions ◽  
Method Of Calculation ◽  
The Road ◽  
Rigid Pavements ◽  
Load Carrying ◽  
Number Of Cycles ◽  
New Criterion

Domestic methods of designing and calculating non-rigid pavements were modified in parallel with changes in the load-carrying capacity of vehicles and an increase in the average traffic intensity of cars. With the increase in the level of costs for the construction and repair of road clothes, the level of responsibility for design has increased. However, more often at the operational stage, early defects of asphalt-concrete layers are detected and premature reduction of the bearing capacity of the structure as a whole. This only indicates that the prediction of the service life in the design of traditional methods is not reliable. The reasons for this may be several: erroneous determination of the number of cycles of the annual loading of the structure, a distorted or ineffective consideration of the climatic conditions of operation of the road-building materials of the layers, an inaccurate technique for determining the maximum permissible and emerging deformations, and also accumulating them during operation. As a result, the issues of construction of road clothes, requirements for them and the design of highways in general are being revised. Obviously, the traditional method of calculation, as a minimum, can not be considered universal. The authors presented a new approach to calculating the strength of non-rigid pavements by the criterion of accumulation of fatigue damages of asphalt-concrete layers, which can provide reliable prediction of the pavement life cycle, because it is based on the multifactorial influence of external environmental impact. Modeling such a multifactor process as the life cycle of a design is a complex computational task. Active integration of computer technologies into modern life and construction processes allows solving this task with the help of a computer, by developing application programs. At the department of «Highways» DSTU developed a software package Pavement Life Cycle, able to make calculations based on a new criterion for calculating non-rigid road clothes. The article is part of the dissertation research of the second author.

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